Removal of the alternator cannot be done without removal of the throttle body as well (the instructions fail to mention this). Additionally, there is a metal bracket preventing the removal of the lower bolt that runs from the intake manifold down to the block - I am going to try and pick up a Haynes manual or something and see what that says.
The pictures from this link: http://www.justanswer.com/questions/...-my-2004-chevy (free registration) show what I'm referring to (the last picture in the removal section, same as first picture in the installation section). That long bolt is stopped about 1/4-1/2" from being able to come out. At this point I am thinking the intake manifold must come out as well.
Actually, looking at the picture again, I think maybe that lower bracket piece may come out after all. From what I could see (precious little, even with mirror-on-a-stick and flashlight), that appeared to be a large mount of some sort - but I could be mistaken. Will try again tomorrow and update.
Also - for cars equipped with AC - the AC lines are directly in the way of a clear removal, hence having to remove the TB.
The only thankful note so far is that no bolts have snapped (knock on wood).